Arcing in a generator can lead to extensive damage which in turn can result in long-term costly outage. Internal generator arcing can be caused by insulation failure, copper fatigue failure or voltage breakdown due to reduced clearances between components operating at different voltages. These potentially damaging arcs result in short duration current pulses containing radio frequency signal components which flow in the generator's neutral grounding circuit. An internal arcing condition in a generator results in a higher than normal level of neutral RF current and there is disclosed herein a novel technique utilizing the measurement of the generator's RF neutral current to detect arcing in a generator.
The use of a spectrum analyzer to measure high frequency currents flowing in the neutral lead of a generator to monitor arcing conditions is described in U.S. Pat. No. 4,156,846, issued May 29, 1979, assigned to the assignee of the present invention and incorporated herein by reference.